I also wanted a better sound and went with the Arrow Ti Racing Pipe (71209PR) with a Rexxer. I left the dB killer in. Sounds great, smooths the power out. Make sure you change your air filter to a high flow. I used an K&N. I'm a Mac user so had to borrow a PC to load the Rexxer tune. After that, super easy to load to the bike. The removal of the OEM exhaust and install of the Arrow was super easy. I used a "kit" off of eBay for the O2 sensor removal. Basically some plugs for the header and caps for the wires. The install of the air filter was a PITA. (10 hard to get at screws. Why screws?) I also ditched the evap canister while I was messing around up there too.